Blockchain is an emerging infrastructural technology that is proposed to fundamentally transform the ways in which people transact, trust, collaborate, organize and identify themselves. In this paper, we construct a typology of emerging blockchain applications, consider the domains in which they are applied, and identify distinguishing features of this new technology. We argue that there is a unique role for the HCI community in linking the design and application of blockchain technology towards lived experience and the articulation of human values. In particular, we note how the accounting of transactions, a trust in immutable code and algorithms, and the leveraging of distributed crowds and publics around vast interoperable databases all relate to longstanding issues of importance for the field. We conclude by highlighting core conceptual and methodological challenges for HCI researchers beginning to work with blockchain and distributed ledger technologies.

There is a widespread belief that pervasive technologies will encourage and facilitate partnerships between citizens and civic authorities, enabling individuals to play a greater role in civic planning, service delivery and infrastructure management. However, at present sustained use and perceived value of civic engagement technologies remains low because the design space is poorly understood by system developers who focus almost exclusively on empowering citizens rather than adopting an informed, inclusive approach that addresses the needs of both citizens and civic authorities, and helps establish trusted relationships between these different stakeholders. We report on an extensive study of civic engagement in the domain of public infrastructure maintenance and provide insights into the civic management processes to support future design of trusted civic engagement interactions.

BACKGROUNDWalking school buses (WSBs) offer a potentially healthier way for children to get to school while reducing traffic congestion. A number of pressing societal challenges make it timely to evaluate evidence of their value.METHODSStudies that focused solely on WSBs were identified through online and manual literature searches. Twelve WSB studies involving a total of 9169 children were reviewed. Study aims, designs, methods, outcomes, and barriers and facilitators were examined.RESULTS WSBs were found to be associated with increased prevalence of walking to school and general activity levels although not always significantly. Time constraints emerged as barriers to WSBs, impacting on recruitment of volunteers and children to the WSBs. Facilitators of WSBs included children enjoying socializing and interacting with the environment.CONCLUSIONSPreliminary evidence of the health value of WSBs was demonstrated, along with recommendations for the design of future studies. By tackling barriers of time constraints, volunteer recruitment, and parents' safety concerns while at the same time, increasing convenience and time savings for families, future WSBs are likely to be more sustainable and taken up by more schools. Implications for future innovation in school health were identified.

Driven by changes in working practices and technology trends, organizations are increasingly reliant on mobile workers and the data they capture. However, while significant work has been carried out on increasing the usability of mobile devices and applications, little attention has been paid to the quality of data captured by mobile workers. If this data is inaccurate or untrustworthy, serious consequences can ensue. In this paper we study a system targeted at mobile workers in the highways sector that is deliberately designed to increase the accuracy and trustworthiness of the data collected. The resulting Inspections application has been very positively received by workers and we present lessons that we believe can be applied to other applications of this type.

HighlightsNovel smartphone presentation of experimentally-controlled word lists.Strong temporal contiguity effects in free recall at rates of 1 word per hour.Shallow serial position effects in free recall at rates of 1 word per hour.Shallow primacy effects in serial recall at rates of 1 word per hour.Recency in recognition of experimental words presented over 50 days.

As in all collaborative work, trust is a vital ingredient of successful computer supported cooperative work, yet there is little in the way of design principles to help practitioners develop systems that foster trust. To address this gap, we present a set of design patterns, based on our experience designing systems with the explicit intention of increasing trust between stakeholders. We contextualize these patterns by describing our own learning process, from the development, testing and refinement of a trust model, to our realization that the insights we gained along the way were most usefully expressed through design patterns. In addition to a set of patterns for trust, this paper seeks to demonstrate of the value of patterns as a means of communicating the nuances revealed through ethnographic investigation.

The widespread use of free analytics tools has helped revolutionise the web-enabling developers to gain deep insights into user behaviour. Analytics are also perceived as critical to enabling the next generation of the Internet of Things. However, despite the existence of numerous IoT analytics engines none have had the catalytic effect of web analytics in helping to transform developers' understanding of the systems they create. In this paper we report on our experiences of creating and using a system that looks to repurpose web analytics to enable growth in the future IoT.

Recent work has questioned the largely unconditional nature of charitable donations and explored the value of conditional giving with contemporary donors. In this paper, we extend this work by exploring how to operationalise features of conditionality in charitable giving, situated in the context of large international non-governmental organisations (NGOs). Building on prior engagements with international aid organisations, we present design considerations and a conceptual architecture supporting real-time, conditional giving for individual and institutional donations. Our architecture leverages properties of distributed-ledger technologies (DLT) to empower donors to (i) attach conditions to their donation, (ii) store funds in a secure, decentralised escrow and (iii) automatically release funds once conditions are met. Unlike prior work that envisions radical disintermediation and the removal of intermediate NGOs using DLT, our work recognises the expertise of NGOs in tackling complex global problems and instead investigates compelling new way for charities to increase transparency and accountability by introducing dynamic pledge controls. CCS Concepts: • Social and professional topics → Socio-technical systems; • Human-centered computing → Mobile computing; • Information systems → Collaborative and social computing systems and tools.